MLSS vs SPY: Correlation
Milestone Scientific, Inc. (MLSS) and SPDR S&P 500 ETF Trust (SPY) show a weak relationship: their 3-year correlation of weekly returns is 0.14.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MLSS and SPY?
On 3 years of weekly data the MLSS/SPY correlation comes out at 0.14, weak. Recent behaviour matches the longer record: 0.12 over 1 year against 0.14 over 3. The 5-year figure is 0.22, and annualized covariance runs at 169.4 %².
Out of 10 assets tracked against MLSS, SPY lands near the bottom at #7. Correlation aside, the last 12 months split them widely, with SPY ahead by 36.4 points (-15.8% versus +20.6%). Note the risk asymmetry: MLSS runs 5.8 times the annualized volatility of the other leg, so equal-weighting the two is not an equal-risk position.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
MLSS vs SPY: side by side
| MLSS (Milestone Scientific, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -15.8% | +20.6% |
| 5-year return | -72.6% | +82.4% |
| Volatility (ann.) | 84.1% | 14.5% |
| Beta vs S&P 500 | 0.81 | 1.00 |
| Max drawdown (3Y) | -81.2% | -18.8% |
| Market cap | – | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | US Listed | ETF · US Large Cap |
SPY is a Large Blend fund from State Street Investment Management: $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | MLSS | SPY |
|---|---|---|
| 2022 | -76.7% | -18.2% |
| 2023 | +43.8% | +26.2% |
| 2024 | +39.1% | +24.9% |
| 2025 | -71.9% | +17.7% |
| 2026 | +87.0% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MLSS and SPY good diversifiers for each other?
Yes. With a correlation of 0.14, MLSS and SPY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
FAQ
What is the correlation between MLSS and SPY?
Using weekly returns as of 2026-08-27: 0.14 over 3 years, with 0.12 over the last year and 0.22 over 5 years.
Is SPY a good diversifier for MLSS?
Yes. With a correlation of 0.14, MLSS and SPY have moved largely independently, which makes them a genuinely diversifying pair by historical standards.
What does a correlation of 0.14 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
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Related comparisons
Hubs: MLSS correlations · SPY correlations
